Enercell

Enercell is a battery brand that was sold exclusively by RadioShack at retail stores and online.

In a "battery of the month club" promotion introduced in the 1960s and discontinued in the early 1990s, RadioShack customers were issued a free wallet-sized cardboard card which entitled the bearer to one free battery a month when presented in RadioShack stores.

[1] The free Enercells were individual AA, C or D cells or 9V rectangular transistor radio batteries.

[2] Like the free tube testing [clarification needed] offered in-store in the early 1970s,[3] this small loss leader helped draw foot traffic.

[4] While the "battery of the month" card program ended in the 1990s, the Enercell name remained in use as RadioShack's store brand of dry cells and transistor radio batteries.

Two AA RadioShack Enercell alkaline batteries, as they appeared between the late 1990s and mid-2000s.